The present invention relates generally to a fiber optic device coupling and, more particularly, to a coupling for connecting an optical fiber cable to an electro-optical device which is suitable for both single and multi-channel applications.
Presently, a threaded coupling nut is the most popular means of holding a fiber optic contact relative to an electro-optical device, such as a light-emitting diode or light-receiving device. Typically, parts of coaxial or RF type of electrical connectors, such as those known in the industry as being SMA connectors, have been used for coupling fiber optic contacts and electro-optical devices.
A shortcoming of the coaxial-type coupling is that it is limited to single channel applications which employ only a single contact and corresponding electro-optical device. In such a connector assembly, the contact is normally mounted firmly in a fixed position by suitably arranged shoulders on the contact and the connector housing, so that there is no longitudinal play of the contact which could result in the end of the contact engaging the active end face of the electro-optical device, which typically includes a fragile window which could be damaged if forcibly engaged by the contact.
It would be highly desirable if a coupling of the type to which this invention pertains could employ contacts that are typically utilzied in multi-channel fiber optic connectors, so that a common contact could be used for the connectors and couplings for active devices, and further to allow selective removal of the contacts from multi-channel coupling assemblies. Such selective removal of contacts is permissible with many conventional multi-channel fiber optic connectors. For example, one standard multi-channel fiber optic connector utilizes a contact retention clip to releasably retain the contact in the assembly. Such an arrangement is disclosed in U.S. Pat. No. 3,947,182 to R. L. McCartney, assigned to the assignee of the present application. In the McCartney patent, an O-ring is used in cooperation with a slidable sleeve in which the contact is mounted so that when the mating halves of the connector engage, the contacts will engage with a positive abuttment force due to the compression of the O-ring. The positive engagement of the mating end faces of the contacts is highly desirable in a fiber optic connector to prevent light loss at the interface of the fiber optic cables. In contrast, in a coupling for connecting an optical fiber cable to an electro-optical device, it is desirable to prevent the contact from engaging the active face of the device. Accordingly, it is desirable that the contact not be capable of moving longitudinally in the coupling after it is mounted therein.
It is an object of the present invention to provide a fiber optic device coupling for connecting an optical fiber cable to an electro-optical device in either a single or multi-channel system that allows the use of a standard fiber optic connector contact that is removably mounted in the coupling, yet prevents the contact from forcibly engaging the fragile active face of the device.